Thermostatic circuit breaker



March 17. 1925. 1,530,042

P. GAY

THERMOSTATIC CIRCUIT BREAKER Filed May 23, I 1921 2 J fivsul. ATION 38 .Paul Gay Patented Mar. 17, 1925.

UNITED STATES-PATENT OFFICE.

raULeAY, or anion, enonern.

THERKOST ATIC CIRCUI'F BREAKER.

Application filed m 23, 1921. semi No. 471,577.

on. internal combustion engines, acting to,

stop the engine when the engine has become overheated or when the temperature of-the engine has risen to a predetermined degree.

The general object of this invention is to provide a stop of this character which will actto stop the engine by interrupting the ignition circuit of the engine or which may be used to interrupt a lighting circuit (in caseit be desired merely to givea signal to the driver) when the car becomes overi'heated, that is when the temperature-of the car has risen to a. predetermined degree.

A further object is to provide a mechas nism of this kind wherein the breaking or closing of the circuit is controlled by a thermostat mounted in intimate conjunction 80' with'the engine or any other part which it is desired to prevent from overheating.

And a further object is to provide a construction of this chara ter which will keep or adjusted to stop' the engine at any given. 40

" the switch in the electric circuit open until the engine cools to a predetermined degree and during this time preventing the engine from being-operated. 1

. Another object is to provide a stop of this character so constructed that it may be set degree of heat, and which can be set or adjust-ed to a point where it Wlll not have any effect on the engine Ill case of had connection.

And another object is to provide-an auto matic stop which will not prevent the engine 'or automobile from delivering its full power or speed under normal renditions and will not affect the engine in any way until the same is overheated.

Still another object is to provide a device of this character which may be readily applied to all makes of automobile engines and connected in the ignition circuit thereof or in the lighting, circuit thereof, and which mav be operated either by heat from the engine itself from a bearing or from any other point where overheating would be can for the engine.

Other ob ects will appear in the course of the following description.

My invention is illustrated in the accompanying drawings, wherein 2- Figure 1 is a plan view of my improved engine stop, the glass 42and the ring 43 be- .mg broken away;

Figure 2 is a top plan view with the plate 15 and the parts carried thereby removed to show the thermostat;

Figure 3 is a face view of the member 17 ,Figu

to the engines and motors of different sizes and particularly'to the bolt known as the block bolt. This block bolt is run through this hole to bolt my device to the block of the engine, thus bringing the stopping device in direct contact with the main part of .the engine that is liable to overheat. The

back plate 11 is formed with a plurality of openings 1d illustrated as three in number, and disposed within the wall of the casing 10 is a front plate 15 upon which the switch scale and other like parts are mounted.

Between this plate 15 and the back plate lland within thecasing 10 there is mounted a thermostat which operates a shaft 16 mounted in suitable hearings in the back case and extends out through the front plate. As illustrated, this shaft carries upon it a crescentshaped member 17, one horn or arm of which is. engaged by a resilient strip re 4 is a fragmentary sectional view' ,of the plate 15 and the strip 36, the contact 18 which is attached to tlze wall of the castwo of, the openings '14 are elongated and dispose immediate beneath the resilient strips. 18 and 20, while'an-opening is disposed between thesethe tem )erature of theengine'block or other part wi l directly afi'ect these. thermostatic strips. I do not wish. to be limited 'tofthe m' may be used, the strip 18 actin use-of two thermostatic strips,'a's only, one asa spring, and indeed I do not wish to limited-to this particular construction of thermostat, as any other desired construction of thermostat might housed within the space between theback plate 1L and the front plate 15.

The shaft 16 extends through the notch or opening 22 in the front plate 15 or vthrough any other suitable-a rture and is provided with the depending and 23 which carries a head 24 of insulated material atits extremity; Mounted uponthe face of the plate. 15 and preferably s'lidably mounted thereon for adjustment is an insulating block 25 which carries iipon it an outwardly projecting contact 26 and a. contact spring 27. This springis approximately U-shaped and is attached to or.forms part of a plate 30, attached to the insulating block 25, the

spring extending downward from this plate- 30 and then upward in resilient engagement with the contact 26, then upward above this contact into the pathrof movement of the block 24: on the pointer or hand 23. The

resiliency of thecontact '27 holds this con-' tact in electrical engagement with the contact 26, but when the extremity of the hand 23 strikes this contact 27, it forces itawav.

from the contact 26 and breaks the electrical engagement between these contacts. The

. contact 26 is electrically connected by the insulated wire 31 to an insulated binding post 32, which in turn is connected in the ignition circuit of the engine. The plate 30 which supports thecontact finger 27 isconnected by an insulated wire 33 to the insulated binding post 34, and this binding post perature, the ther ostat will cause the hand,

23 to move to the left in Figure 1, thuscaus ing the finger 27 to again contact the contact 26' and complete the circuit, and the enginewill once more start up. As before remarked, itis.- advisable to have the insulated block 25 slidably mounted for adjustment across the jaw of the ilient strips so thatv to this construction, however. tached to the-plate 35 is a'traveling nut 38 us so long as.

plate 15. To this end, I have illustrated the slidi .block as being mounted upon a plate 35 which is sl-idably' mounted uponthe strip 36, and I have illustrated the plate 15 as carrying :a transversely extending strip 36.. forming a track and the plate 35 as being. "formed with'ears 37extending inward beneath this track. I do not wish to be limited Also atwhich is formed 'of a screw-threaded lug,

and through this'screw-threaded lug ,passes an adjusting screw'39 which, at one end at least, extends out to the exterior of the easing 10 and is provided with a head 40.whereby it-may be readily manipulated and set. Preferably this head 40 is so constructed .that it will requirea screw-driver-or like implement to rotate it in order that this screw .39 may not be turned accidentally.

Disposed upon thebase of the plate 25 andbeneatli the finger 27 is a transversely extending scale 41, and by rotating the screw .39 the sliding carrier which carriesthe contacts 26 and 27 -may be adjusted with reference to this scale, the finger 27 forming an index pointer which coacts with the scale or graduations It will be obvious now that the further over toward the right that the slide is moved, the higher will be the temperature necessary in orderfor the inter 23 to contact with the finger 27 an break theignition circuit, and that the further toward theleft the slide is moved, the less increase in temperature will be necessary in order to cause the pointer 23 to break the circuit. The slideis' graduated in degrees,- as for instance from 100 to 150,

"there being.graduations indicating every 100 and every 50, and thus it is an easy matter to adjust this automatic stop so that it will break the circuit through the engine when the temperature of: the engine block or other part has risen to the predetermined degree.

I do not wish to be limited to any particular circuit in which this device may be connected, but I contemplate the; binding post 34 as being connected to the -breaker box or magneto post of the engine, while the wire from'the post 32 may be connected course, used where the engine uses a ma tlo for generating the electricity for the igniti on circuit, but is purely illustrative of one "application of this device, as this wiring might be readily changed. The casing is, of course, provided with .a glasspane42 held in place in any suitable manner, as by a ring 43, thus permitting the scale41 to be read and the sliding -t0 the induction coil. This wiring is, oi.

blockcarrying the contacts tobeadjusted. I

It will lie-noted that the contact 27 :constitutes a resiliently actuated switch project- ,ing into the path of movement .0.the.hand

"so forming the finger 23, this switchbeing shifted out of its circuit closing position by the hand 23 and being resiliently urged to its circuit-closing position.

\Vhile I design this device to be used in connection with an ignition circuit of any automobile in order to provide an automatic stop which will positively stop the engine when a certain temperature has been reached, itis obvious that the breaking of the circuit might cause a certain signal to be given whereb the driver is made aware of the fact hat the engine is overheated, and it is obvious also that the same mech anism might be'used to complete a circuit through a signal when the temperature had risen to a predetermined degree instead of breakingthe circuit through the signal'by 27 that it would be normally outof contact with the contact 26 and causing the pointer 23 to close the finger against the contact 26 when the predetermined temperature was reached. Neither do I wish to be limited to the details of construction or arrangement of parts, as illustrated, as these might be varied in many ways without departing from the spirit of the invention.

I claim:- A thermostatic circuit closer of the character described comprising a casing, a shaft disposed within the casing, a rocker mounted upon said shaft and having extensions projecting toward each other, a pair of thermostatically shiftable elements mounted upon the casing at one end and at their free ends engaging the inwardly projecting portions of said rocker whereby u on an expansion of said elements the roc or will be shifted in one direction and upon a contraction of the elements the rocker will be shifted in the other direction, a hand carried upon said shaft, a slide, a vieldable con tact mounted upon the slide for movement therewith and constituting a pointer, a scale PAUL GAY. 

